Speech in key words

Security has been very tight across Beijing, with many dissidents detained or under house arrest, rights groups say.

On Thursday, Mr Hu told delegates at the Great Hall of the People that China had to adapt to a changing domestic and global environment.

"We must aim higher and work harder and continue to pursue development in a scientific way, promote social harmony and improve the people's lives," he said.

China's development should be made more balanced and sustainable, he said, and the "serious challenge" of corruption should be addressed.

"If we fail to handle this issue well, it could prove fatal to the party, and even cause the collapse of the party and the fall of the state," he said.

Anyone who broke the law would be brought to justice, "whoever they are and whatever power or official positions they have", he said.

The corruption warning echoed one delivered 10 years ago during the previous leadership transition, when the party was told it risked "heading for self-destruction" if it did not tackle the issue.

The months leading up to the 18th party congress have seen China's political leadership rocked by a scandal involving Bo Xilai, the former Chongqing party leader once seen as a candidate for top office.

His wife has been jailed for murdering a British businessman and he is expected to face trial on corruption-related charges.

Analysis

By Kerry BrownProfessor of Chinese politics, University of Sydney

All the standard slogans we have become familiar with during the Hu Jintao period got an airing in his speech. "Peaceful development", "creating a beautiful China", "firmly marching on the path of socialism with Chinese characteristics".

There was the familiar stress on needing to have stability and security in society, and to support the military, nurture good relations with Taiwan across the Strait and, perhaps with a little more force than it would have usually been given in view of the Bo Xilai events, a section on the need to do something about corruption.

All it really tells us is that, till the last, Hu Jintao has been a man of immense political and personal self-control. His legacy will be consensus-led, collective leadership in an age in which Chinese society was undergoing fast, profound and disorientating changes.

Across China, meanwhile, recent cases of official corruption have stoked public anger and there have been a series of high-profile mass protests focusing on land grabs and environmental issues.

On the internet, thousands of people have called for better measures to fight corruption, leaving comments on websites launched for the congress by official media outlets Xinhua news agency, People's Daily and China Central Television (CCTV).

Economic growth has also slowed in recent months and the wealth gap is an issue of great concern, as is China's ageing population.

Mr Hu said a new model for economic growth was needed to respond to domestic and global changes.

"On the basis of making China's development much more balanced, coordinated and sustainable, we should double its 2010 GDP and per capita income for both urban and rural residents (by 2020)," he said.

The president also said that China would continue what he described as "the reform of the political structure", but stressed that Beijing "will never copy a Western political system".

Amid rumbling regional tensions over territorial rows in the East China and South China Sea, Mr Hu said the nation should "resolutely safeguard" maritime rights and become a maritime power.

'Growing concerns'

The congress - for which no formal schedule has been revealed - will last a week and will be keenly observed for any indications of the leadership's future plans.

China's leadership change

Special Communist Party meeting every 10 years

This time, leaders over age of 68 will be retired

New group of seven or nine top leaders unveiled

Names already decided in secret, none elected

Factions more important than policies, exact selection process unclear